Courio (sendcourio.com) for ChatGPT

si.courio/courio

Courio (sendcourio.com): mail real paper letters (standard, registered) worldwide. No account.

client:ChatGPT transport:streamable-http tools:5

Install Courio (sendcourio.com) in ChatGPT

Settings → Connectors → Advanced → Developer mode

https://api.sendcourio.com/mcp

Custom connectors are a paid-plan feature and take a remote URL only. ChatGPT cannot run a packaged server locally. ChatGPT docs